1. Field of the Invention
The present invention relates to an electrical connector for insulated cable. More particularly, it relates to a connector which can be utilized without tools to quickly and effectively make an electrical connection to a hot conductor wire, a neutral conductor wire and a ground wire which are encased in an outer sheath of a transversely cut unstripped end of insulated electrical cable.
2. Prior Art
It has long been known to provide a body member having a pivotally mounted lid having blade members therein to make an electrical connection to an electrical cord by piercing the insulation with the blade members. An example of such a device is shown and described in Greenbaum, U.S. Pat. No. 2,717,365. The Greenbaum device is effective for quickly attaching an outlet receptacle and a product manufactured in accordance with the teachings of such patent is still being sold as catalog number BP2603B and part number 2603H of Eagle Electric Mfg. Co., Inc. While useful for a limited purpose, such device has severe limitations. First, it is designed solely for use on an electric cord having two insulated wires (in the form of a standard lamp cord). Even within such limited range of use, with such cords may not be utilized on very small width cords such as type “TPT” (used on electric shavers) or type “XT” (used on tiny Christmas lights). Further, such device is not designed for use and may overheat if used in connection with broilers, toasters, irons or other devices rated over 1250 watts (10 amps and 125 volts).
The present invention on the other hand does not relate to a connector for lamp cord but rather relates to an improved device for making an electrical connection to an unstripped end of an insulated electrical cable of the Romex type which has an outer sheath within which an insulated hot wire, an insulated neutral wire, and a ground wire are enclosed. Providing a reliable connector which, with separate blade members, pierces through both the outer sheath and the separate layer of insulation on the hot and neutral wires and makes a connection with such wires, and which also cuts through and makes a reliable connection with a separate ground wire contained in the cable is a far more difficult task.
Additional background of the present invention and prior art applicable to the present invention is discussed in detail in Libby, U.S. Pat. No. 5,785,551 and Libby, U.S. Pat. No. 5,975,938. The complete specification of each of these patents is hereby incorporated herein by reference thereto.
Libby, U.S. Pat. No. 5,785,551 teaches that it is desirable to reduce and simplify the number of steps required in wiring an electrical power distribution system and to make electrical connections without the need to strip the ends of the individual conductors in an electrical cable. FIGS. 13a through 13d show and describe a device used to make an electrical connection to a transversely cut unstripped end of insulated electrical cable having at least two individually insulated conductors which are encased in an outer sheath. With that system, a special pair of pliers is utilized to drive generally parallel spaced apart individual blade members downwardly through the outer sleeve of the cable, through the conductor insulation and into an electrical connection, respectively, with each of the wire conductors.
Libby, U.S. Pat. No. 5,975,938 teaches the provision of an electrical connector for insulated cable including a body, a pair of arm members, a pair of electrically conducting blade members, an electrical output means and an electrical pathway between the blades and the output means. When the arm members are moved from an open position to a closed position with an unstripped end of insulated electrical cable present in the cavity, the blade members cut through the outer sheath of the cable and also cut through the insulation of the individually insulated conductors and the blades move to a location where said blade members are in electrically contact with said conductors. While generally effective, the provision of separate arm members adds unnecessary complexity to the connector and the design shown may not always make a reliable connection to an unstripped ground wire in the cable.
Thus, while these systems are functional and each constitutes an improvement over the prior art, there remains a need for a more effective, more expedient and less expensive connector which can make a reliable connection to an insulated hot wire, an insulated neutral wire and to a ground wire present within an outer sheath of an unstripped electrical cable.